src/src/routers/rf_get_errors_address.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2009 */
   6 /* See the file NOTICE for conditions of use and distribution. */
   7
   8 #include "../exim.h"
   9 #include "rf_functions.h"
  10
  11
  12 /*************************************************
  13 *        Get errors address for a router         *
  14 *************************************************/
  15
  16 /* This function is called by routers to sort out the errors address for a
  17 particular address. If there is a setting in the router block, then expand and
  18 verify it, and if it works, use it. Otherwise use any setting that is in the
  19 address itself. This might be NULL, meaning unset (the message's sender is then
  20 used). Verification isn't done when the original address is just being
  21 verified, as otherwise there might be routing loops if someone sets up a silly
  22 configuration.
  23
  24 Arguments:
  25   addr         the input address
  26   rblock       the router instance
  27   verify       v_none / v_recipient / v_sender / v_expn
  28   errors_to    point the errors address here
  29
  30 Returns:       OK if no problem
  31                DEFER if verifying the address caused a deferment
  32                  or a big disaster (e.g. expansion failure)
  33 */
  34
  35 int
  36 rf_get_errors_address(address_item *addr, router_instance *rblock,
  37   int verify, uschar **errors_to)
  38 {
  39 uschar *s;
  40
  41 *errors_to = addr->prop.errors_address;
  42 if (rblock->errors_to == NULL) return OK;
  43
  44 s = expand_string(rblock->errors_to);
  45
  46 if (s == NULL)
  47   {
  48   if (expand_string_forcedfail)
  49     {
  50     DEBUG(D_route)
  51       debug_printf("forced expansion failure - ignoring errors_to\n");
  52     return OK;
  53     }
  54   addr->message = string_sprintf("%s router failed to expand \"%s\": %s",
  55     rblock->name, rblock->errors_to, expand_string_message);
  56   return DEFER;
  57   }
  58
  59 /* If the errors_to address is empty, it means "ignore errors" */
  60
  61 if (*s == 0)
  62   {
  63   setflag(addr, af_ignore_error);      /* For locally detected errors */
  64   *errors_to = US"";                   /* Return path for SMTP */
  65   return OK;
  66   }
  67
  68 /* If we are already verifying, do not check the errors address, in order to
  69 save effort (but we do verify when testing an address). When we do verify, set
  70 the sender address to null, because that's what it will be when sending an
  71 error message, and there are now configuration options that control the running
  72 of routers by checking the sender address. When testing an address, there may
  73 not be a sender address. We also need to save and restore the expansion values
  74 associated with an address. */
  75
  76 if (verify != v_none)
  77   {
  78   *errors_to = s;
  79   DEBUG(D_route)
  80     debug_printf("skipped verify errors_to address: already verifying\n");
  81   }
  82 else
  83   {
  84   BOOL save_address_test_mode = address_test_mode;
  85   int save1 = 0;
  86   int i;
  87   const uschar ***p;
  88   const uschar *address_expansions_save[ADDRESS_EXPANSIONS_COUNT];
  89   address_item *snew = deliver_make_addr(s, FALSE);
  90
  91   if (sender_address != NULL)
  92     {
  93     save1 = sender_address[0];
  94     sender_address[0] = 0;
  95     }
  96
  97   for (i = 0, p = address_expansions; *p != NULL;)
  98     address_expansions_save[i++] = **p++;
  99   address_test_mode = FALSE;
 100
 101   /* NOTE: the address is verified as a recipient, not a sender. This is
 102   perhaps confusing. It isn't immediately obvious what to do: we want to have
 103   some confidence that we can deliver to the address, in which case it will be
 104   a recipient, but on the other hand, it will be passed on in SMTP deliveries
 105   as a sender. However, I think on balance recipient is right because sender
 106   verification is really about the *incoming* sender of the message.
 107
 108   If this code is changed, note that you must set vopt_fake_sender instead of
 109   vopt_is_recipient, as otherwise sender_address may be altered because
 110   verify_address() thinks it is dealing with *the* sender of the message. */
 111
 112   DEBUG(D_route|D_verify)
 113     debug_printf("------ Verifying errors address %s ------\n", s);
 114   if (verify_address(snew, NULL,
 115       vopt_is_recipient /* vopt_fake_sender is the alternative */
 116       | vopt_qualify, -1, -1, -1, NULL, NULL, NULL) == OK)
 117     *errors_to = snew->address;
 118   DEBUG(D_route|D_verify)
 119     debug_printf("------ End verifying errors address %s ------\n", s);
 120
 121   address_test_mode = save_address_test_mode;
 122   for (i = 0, p = address_expansions; *p != NULL;)
 123     **p++ = address_expansions_save[i++];
 124
 125   if (sender_address != NULL) sender_address[0] = save1;
 126   }
 127
 128 return OK;
 129 }
 130
 131 /* End of rf_get_errors_address.c */